I'm not sure. Maybe you can change the hackerearth account name by clicking the top right corner of web page.

On the top right you will find your profile page button. When you click on it, it will bring you to your profile page. ON your profile page, you will see your profile picture and name on the left side. There will be a "edit" icon (the shape of a pencil) at the corner of that area. Click on that, and you can change your name.

so do I